Visual Basic - guardar foto de datagridvieew a base de datos

Estimados colegas tengo un datagridview con datos y una fotografia la cual quiero guardar en la base de datos sqlserver, pero no se como guardarla.

tengo el siguiente codigo en el form.

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

Dim f As FUNCIONES
f = New FUNCIONES()

Dim mc2 As crendicion
mc2 = New crendicion()


mc2.gfecha_rendi = DateTimePicker1.Value // esto si me lo guarda
mc2.gid_persona = TextBox1.Text // esto igual me lo guarda a la base de datos.


Dim registro As List(Of Cregistro_rendi)
registro = New List(Of Cregistro_rendi)

For Index As Integer = 0 To DataGridView1.RowCount - 1

Dim dc2 As Cregistro_rendi
dc2 = New Cregistro_rendi

Dim num_llamado As Integer
num_llamado = DataGridView1.Rows(Index).Cells(0).Value.ToString()

Dim fecha_boleta As Date
fecha_boleta = DataGridView1.Rows(Index).Cells(1).Value.ToString()

Dim n_dcto As String
n_dcto = DataGridView1.Rows(Index).Cells(2).Value.ToString()

Dim valor As Integer
valor = DataGridView1.Rows(Index).Cells(3).Value.ToString()

Dim detalle As String
detalle = DataGridView1.Rows(Index).Cells(4).Value.ToString()

/// aqui es donde tengo que convertir la foto para guardarla a la base de datos.

dc2.gnum_llamado = num_llamado
dc2.gfecha_t_reg_rendi = fecha_boleta
dc2.gboleta = n_dcto
dc2.gvalor = valor
dc2.gdetalle = detalle
dc2.gtotal = TextBox10.Text
dc2.gfoto = // aqui no se que tiene que ir

Next
f.INSERTAR_RENDICION(mc2, registro)

End Sub


________________________________________

y esta es mi clase

Imports System.Data
Imports System.Data.SqlClient

Public Class Cregistro_rendi
Private id_rendicion As Integer
Public Property gid_rendicion() As Integer
Get
Return id_rendicion
End Get
Set(ByVal value As Integer)
id_rendicion = value
End Set
End Property

Private fecha_t_reg_rendi As Date
Public Property gfecha_t_reg_rendi() As Date
Get
Return fecha_t_reg_rendi
End Get
Set(ByVal value As Date)
fecha_t_reg_rendi = value
End Set
End Property

Private nboleta As Integer
Public Property gboleta() As Integer
Get
Return nboleta
End Get
Set(ByVal value As Integer)
nboleta = value
End Set
End Property

Private valor As Integer
Public Property gvalor() As Integer
Get
Return valor
End Get
Set(ByVal value As Integer)
valor = value
End Set
End Property

Private detalle As String
Public Property gdetalle() As String
Get
Return detalle
End Get
Set(ByVal value As String)
detalle = value
End Set
End Property

Private num_llamado As Integer
Public Property gnum_llamado() As Integer
Get
Return num_llamado
End Get
Set(ByVal value As Integer)
num_llamado = value
End Set
End Property

Private total As Integer
Public Property gtotal() As Integer
Get
Return total
End Get
Set(ByVal value As Integer)
total = value
End Set
End Property

Private foto_boleta As Image
Public Property gfoto_boleta() As Image
Get
Return foto_boleta
End Get
Set(ByVal value As Image)
foto_boleta = value
End Set
End Property
End Class